Submersible water pumping system



1956 E. J. SCHAEFER SUBMERSIBLE WATER PUMPING SYSTEM INVENTOR.uardfifflcfmefe Filed April 25, 1954 United States P en 2,734,462SUBMERSIBLE WATER PUMPING SYSTEM Edward J. Schaefer, Fort Wayne, Ind.Application April 23, 1954, Serial No. 425,151

2 Claims. Cl. 103-223 This invention relates to improvements in waterpumping systems and more particularly to a novel pressure storage meansfor such a system.

The usual home water system comprises a motor driven pump arranged'topump water from the well and discharge it into an aircontaining pressuretank from which the water passes into the various service lines. Thepump is automatically started and stopped by a control switch responsiveto the pressure in the tank or the pump discharge so that a bulk supplyof water under pressure is maintained at all times in the tank and isready for instant use upon withdrawal through the service line.

Such systems have several well known drawbacks. In the first place, theinitial supply of air in the pressure tank gradually becomes absorbed inthe water so that the cushioning effect is lost and the system issaid'to become water-logged as reflected by erratic operation andfrequent starting and stopping of the pump. Accordingly, air injectionmeans must be provided for replenishing the air in the pressure tank asrequired. However, this arrangement is often unreliable and necessitatesfrequent maintenance and attention. Another objection to theconventional pressurized water system is that the relatively largevolume of water retained in the pressure tank tends to become stalesince the tank is rarely emptied. The fresh incoming water is mixed withthe water in the tank so that the water passing to the service lines isnever completely fresh water.

In addition to the foregoing problems, there has been an increasingdemand for a simplified or so-called packaged unit which can beinstalled with a minimum of electrical and plumbing connections.

A primary object of my invention is to provide a novel simplified watersystem capable of being sold and installed as a packaged unit.

A further object of the invention is to provide a novel submersiblewater system in which the major components of the system are adapted tobe located in the well below the ground level.

An additional object of the inventionis to provide a novel packagedwater system having a submersible unit adapted to be lowered into a welland prepared for operation merely by making electrical and outlet pipeconnections from above ground.

Another object of the invention is to provide an improved water pumpingsystem having novel pressure storage means for maintaining a supply ofwater under pressure.

Still another object of the invention is to provide a novel and improvedwater system which cannot become water logged, which does not requirereplacement of cushioning air, and which supplies substantially freshwater at all times.

Other objects and advantages of the invention will become evident fromthe subsequent detailed description taken in conjunction with theaccompanying drawing, wherein:

Fig. 1 is a fragmentary longitudinal sectional view of ice a unitcomprising one specific embodiment of the invention and having a motordriven pump and a pressure storage means;

Fig. 2 is a view similar to Fig. 1 but showing a different operatingcondition of the pressure storage means; and

Fig. 3 is a transverse sectional view as taken along the line 3-3 ofFig. l. i

Referring to the drawing, one specific embodiment of the invention whichis shown merely by way of illustration comprises a motor driven pump,unit indicated generally at 11 and having an electric motor section 12and a pump section 13 with adischarge outlet 14. The motor and pumpsections 12 and 13 are contained within an outer casing or housing 16which renders the unit submersible. A check valve or foot valve 17 ismounted in a partition 18 in the upper end of the housing 16 forpreventing loss of fluid head in the usual manner.

Immediately adjacent the upper or outlet end of the motor driven pumpunit 11, I provide a pressure storage tank designated generally at 19,which constitutes the principal novel feature of my invention. Thepressure storage tank 19 comprises an elongated tubular metal casing 21having an apertured metal closure or head 22 at its lower end and asimilar closure or head 23 at its upper end. The apertured head members22 and 23 provide a fluid inlet and outlet, respectively, for thepressure tank and are formed with integral axially extending tubularstubs 24 and 26 which are internally threaded. The pressure tank 19 isconnected in the water system by means of a threaded nipple 27 securedto the inlet stub 24 and also to a threaded outlet member 28 at theupper end of the motor-pump unit 11. The outlet stub 26 from thepressure storage tank 19 has a threaded con nection with a dischargeline 29, it being understood that the motor pump unit 11 and itsinterconnected pressure storage unit 19 will be disposed in the wellwith the discharge line 29 extending upwardly therefrom to the groundlevel for connection to various service lines.

Within the pressure tank 19 tube 31 is disposed inaxially extendingrelation with the outer concentric casing 21 spaced radially therefrom.The tube 31 may be made of any suitable water and air imperviousmaterial which is also flexible and elastic, e. g. natural or syntheticrubber or the like. The opposite ends of the tube 31 have annular flangeportions, as at 32 and 33, which seat against complementary radialshoulder portions 34 and 36 surrounding the openings in the inlet andoutlet members 22 and 23, respectively. For insuring an air and watertighthermetic seal between the expansible tube 31 and the outer rigidcasing of the pressure tank 19, a sealing gasket 37 is placed againstthe outer axial end of each of the tube flanges 32 and 33 and a tightsealing connection is obtained byscrewing the connecting nipple 27 andthe discharge line 29 tightly into the threaded stubs 24 and 26 so as toclamp the flanged ends of the tube 31 against the shoulders 34 and 36.

From the foregoing description, it will be seen that the elastic andexpansible tubular member 31 is disposed directly in the path of flowbetween the pump unit and the discharge line 29 for conveying pumpedwater therethrough, and at the same time the tube 31 is in hermeticallysealed relation with respect to the outwardly spaced rigid container21-42-23. The annular space, designated at 38, between the tube 31 andthe wall of the pressure tank 19 contains a fixed quantity of air, andtherefore, functions as an air compression or cushioning chamber. InFig. l, the device is shown with the central expansible tube 31 in itsnormal unexpanded condition which might correspond to a situation wherethe pump is in operation and the service outlets are fully open so thatthere is insufficient back pressure to cause expansion of the anelongated expans ible tube 31. However, in Fig. 2 the apparatus is shownwith the central tube 31 in radially expanded condition as might be thecase when the service outlets are fully closed and the pump has operatedfor a sufficient time to build up pressure within the pressure storagetank 19. As the outlet water pressure increases, the tube 31 expandsradially and thereby compresses the fixed quantity of air contained inthe annular chamber 38 whereby the water in the expanded tube ismaintained under pressure.

A pressure control arrangement of the usual type will, of course, beprovided for regulating the pressure in tne storage capacity regionwithin the expanded tube 31. Thus, in Fig. 1, I have shown in schematicfashion a control unit 39 which would ordinarily (but not necessarily)be located at the ground level and which has an electrical connection 41with the motor section 12 and a fluid connection 42 with the dischargeline 29. Obviously, the connection 42 which reflects the pressure in thesystem could also be made with the air cushion within the space 38. Asis well known in this art, the controller 39 comprises a pressureresponsive switch which can be set to start the motor pump unit when thepressure in the system falls below a predetermined level and which alsofunctions to stop the pump when the pressure reaches a predeterminedmaximum. For example, a convenient adjustment of the control 39 for ahome water system would be to have the pump start when the tank pressuredrops to 20 pounds per square inch and to have the pump stop when thepressure rises to 40 pounds per square inch. Thus, the expansible tube31 having the confined air cushioning means disposed therearound isinterposed directly in the path of flow of the discharge water from thepump and functions to provide pressure storage capacity for the systemin a unique and highly convenient manner.

As will be readily apparent, the foregoing arrangement has a number ofadvantages not heretofore conveniently available in water pumpingsystems of this general character. In the first place, the fixedquantity of cushioning air contained in the sealed space 38 is sealedoff from the water in the system so that there is no possibility of theair being absorbed in the water and lost from the system. Thus, thereare no difficulties with water-logged operation in my invention and itis not necessary to provide special air injection means for replenishinglost air. It will also be seen that because the pressure storage regionis interposed directly in the path of flow between the pump and thedischarge line there is a minimum opportunity for water to be retainedin the pressure storage region and thereby become stale. On thecontrary, with my invention the pressure storage tank will frequently becompletely emptied during normal usage of the water system so thatcomparatively fresh water is usually available.

Another highly important advantage of the invention is the eliminationof the separate pressure tank in its usual form as heretofore known.With the present invention, the pressure storage tank is integrallyconnected to the pump so as to provide in effect a combined packagedunit which includes all of the essential components of the water system.Inasmuch as the arrangement herein described is a completely packagedsystem, the combined unit can be lowered into the well and put intooperation in a very simple manner merely by making the necessaryelectrical and service line connections at the ground level. Thus, boththe motor-pump unit and the pressure storage unit are integral parts ofa completely submersible system.

Although the invention has been described above in connection with aparticular specific embodiment thereof, it will be understood thatvarious modifications and equivalent structures may be resorted towithout departing from the scope of the invcniton as defined in theappended claims.

I claim:

1. A submersible unitary water pumping and pressure storage apparatusadapted to be lowered into a well comprising elongated motor-pump meansdisposed at the lower end of the apparatus and having a water outlet atits upper end, and pressure storage means disposed above said motor-pumpmeans at the upper end of the apparatus, said pressure storage meansincluding an elongated rigid tubular casing connected at its lower endto said motor-pump means at said outlet, connector means providing afluid flow connection at the upper end of said casing for connecting thesame to a discharge line, an elongated resilient expansible tubedisposed axially in said casing in annularly spaced relation therefrom,said tube being disposed in the path of flow from said outlet to saidconnector means for passage of pumped water therethrough, and means atthe opposite ends of said tube providing a seal with said casing wherebyto define an annular air compression chamber between the tube and saidcasing, the size of said pressure storage means being sufiicientrelative to the fluid capacity of the motor-pump means so that theinternal volume of said expansible tube is adequate to provide apressurized water storage chamher under the pressure of said expansibletube and the air in said compression chamber when the tube is expanded.

2. The structure of claim 1 further characterized in that said tubularcasing is provided at its upper and lower ends with relativelyrestricted diameter tubular extensicns, the extension at the lower endof the casing being connected to the outlet of said motor-pump means andconstituting the sole support for said motor-pump means, the extensionat the upper end of the casing comprising said connector means wherebythe apparatus is adapted to be suspended solely from the discharge line,and said tube being disposed in fluid communication between saidextensions for passage of water therethrough.

References Cited in the file of this patent UNITED STATES PATENTS 17,726Clark July 7, 1857 1,579,891 Sandoz Apr. 6, 1926 1,957,320 Coberly May1, 1934

